Pevsner's London 2: South (with Bridget Cherry, 1983) says:
DIXCOTE, North Drive [Streatham Park], of 1897 for R W Essex, was designed by Voysey but executed by Water Cave. It is Voysey’s largest London house, a little crammed in, but of the happy rambling composition characteristic of the great architect; also one of his typical massive, trustworthy chimneys. (Good staircase).
Although Pevsner refers to the house as Dixcote, the name appears in Voysey's Black Book and is carved on the inner porch without the 'e'.
(Source Voysey Society)